There has been known that a microwave can coagulate (immobilize) body tissues such as digestive organs, a liver, a bladder, a prostate, a uterus, blood vessels, and intestinal tracts at low temperature. Then, various devices for assisting surgery through use of the microwave have been developed.
In Patent Literature 1, there is disclosed a microwave-irradiating apparatus including a probe having an elongated shaft (14). The shaft includes a tubular outer peripheral wall (18), a radiation part (15) arranged at a tip end of the shaft (14), a transmission line (17) extending to the radiation part in the tubular outer peripheral wall (18), and an elongated branching member (19) extending together with the transmission line (17) in a vertical direction of the shaft (14). A side wall of the transmission line (17) and a side wall of the branching member (19) are held in contact with each other and held in contact with an inner surface of the tubular outer peripheral wall (18) at two separate different positions, to thereby provide a pair of liquid current passages (20, 21) in the shaft (14). At a time of use, a cooling liquid flows down through one of the passages (20) and returns through the other passage (21).
In Patent Literature 2, there is disclosed a microwave-irradiating apparatus including a hollow electrode capable of supplying a medicine to a microwave-irradiating part.
However, in any of the patent literatures of the related art, there are neither disclosed nor suggested a microwave-irradiating instrument including a central conductor forming a channel, the instrument having a coaxial cable shape, and further the instrument serving as forceps, scissors, or a knife according to the present invention.